Adds +2 to Constitution (thus adding +1 to Fortitude saving throws and +1 to max HP per character level) but suffer -2 to Strength (thus suffering a -1 To Hit in melee and -1 Damage with melee and thrown weapons)
Strength
Adds +1 to Dexterity (thus, depending on prior Dexterity score, adding either 0/+1 To Hit with ranged attacks, either 0/+1 to AC, and either 0/+1 to Reflex saving throws) and suffer -1 to Strength (thus, depending on prior Strength score, suffering either 0/-1 To Hit in melee and either 0/-1 Damage with melee and thrown weapons)
Adds +2 to Dexterity (thus adding +1 To Hit with ranged attacks, +1 to AC, and +1 to Reflex saving throws) and –2 to Strength (thus suffering a -1 To Hit in melee and -1 Damage with melee and thrown weapons)